I remember the power limitations were either a .61 2 stroke or a 1.20 4 stroke engine. In Classic Pattern, is a 1.20 2 stroke engine acceptable? The reason I ask is that I have a Boxer 1.20 partially built. with a Bully (Webra) 1.20 2 stroke for power. This plane was part of the evolution to what is now the 2 meter airplane, although it's only a big sister to the Boxer 60, and not a true 2 meter airplane.